The Biostatistics Core will provide essential biostatistical support to investigators on the Northwest Prostate Cancer SPORE. This Core will link study design, data collection, measurement, and analysis to the critical hypotheses and questions of the Northwest Prostate Cancer SPORE through the following Specific Aims: 1. Study Design: Define study hypotheses, study populations and experimental parameters to answer the research questions of interest, reduce systematic bias and ensure a high likelihood of detection of biologically meaningful effects. 2. Analysis and Interpretation: Identify and implement state-of-the-art quantitative methods to address the scientific questions of interest and provide valid statistical inferences about the evidence supporting the various study hypotheses. Provide necessary bioinformatics expertise for study interpretation. 3. Methods Development: Where appropriate statistical methods are inadequate or lacking, devise and implement novel quantitative approaches to address study questions of interest. During the prior funding periods, the Biostatistics Core played an integral role in the collection, validation and analysis of data for SPORE projects. Our experience has shown that involvement of statisticians from the concept phase yields studies that are better designed, more likely to answer the scientific questions of interest, and, ultimately, more compelling in their conclusions. Therefore the Core will continue to function though close collaboration with investigators from the beginning through the life of each SPORE study. The Biostatistics Core operates from within the Biostatistics Program at the FHCRC. Investigators on the Core play leadership roles on funded studies and programs whose missions overlap considerably with that of the Core. These include the Data management and Coordinating Center for the Early Detection Research Network, and the Program in Computational Biology and Bioinformatics at the FHCRC. Access to and collaboration with these programs will enhance the Core's ability to address analytic questions raised by SPORE studies using cutting-edge, and, if necessary, novel techniques.